10 YEARS AGO — 2002
Segway’s secret: cleverly wound servos: The Human Transporter from inventor Dean Kamen gets its power from special brushless servo technology. The Rockford, Ill.-based Pacific Scientific Div. of Danaher Motion created a new sensor design for the Segway that allows feedback to the motor-drive electronics without an encoder or resolver. A patented hemispherically wound stator features redundant windings. which effectively realizes two functioning motors in one shell. If one set of windings fails, the motor continues to operate. An added benefit of this technology — a smaller motor. Pacific Scientific also devised a proprietary process to injection mold key motor components and encapsulate windings in one step. The motor is said to have 40% more torque than comparable motors.
30 YEARS AGO — 1982
Sled to prove M-X missile system: A rocket sled being developed will subject the guidance system of the M-X missile to the inertial loads it will encounter during launch and ascent. At the Air Force’s Arnold Engineering Development Center, a 5%-scale model of the sled was studied at five Mach numbers ranging from 1.5 to 2 to obtain aerodynamic data needed in the design of the full-scale vehicle. The model was mounted in close proximity to a ground plane simulating the dual-rail, high-speed test track at Holloman AFB, where the complex M-X guidance and control system will be tested.
50 YEARS AGO — 1962
A gas-turbine prototype, the Rover T4 is designed “with the possibility of future production in mind.” The Rover Co. Ltd., which has been researching gas-turbine engines for over 15 years, says that considerable technical advances have been made, particularly in improved fuel consumption and throttle response to provide fast acceleration. In addition to its unconventional powerplant, the four-passenger T4 has all-round independent suspension and disc brakes.